Portable electric heater



FIG. 1 is a plan view of a portable electric heater, showing my new design;

FIG. 2 is a front side elevational view thereof;

FIG. 3 is a rear side elevational view thereof;

FIG. 4 is a right side elevational view thereof; and

FIG. 5 is a left side elevational view thereof. 

The ornamental design for a portable electric heater, as shown and described. 